Raining in the Bivy Sack

Simply a matter of a lack of ventilation. You might check the weight of your bivvy and then decide if one of the quite nice one man tents on the market might be worth the money. There's a number of one-man tents that will be much more comfortable than a bivvy that are right at 2 lbs. The goretex bivvy I used was heavier than the the TarpTent Rainbow I use now, which has a 40" x 88" floor with several pitching options, good ventilation and room for larger LR rifle and full pack completely inside the tent with me. At just under 2 lbs. that's hard to beat as are the other options mentioned by others here. A true double wall tent will most always be a little dryer than a single wall. No going back to the bivvy for me unless the terrain absolutely demands it.

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In the beginning God created the heavens and the earth. Genesis 1:1

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